The Zombies were knocked over and burned by the wall as the cannon had knocked some of the Zombies to parts
The Lich had avoided the attack to him as a ball of dark energy came around the tip of his staff. The high-ranking Zombie had fired it at Pastoval. He didn't seem to pay much attention to the skeleton, just assuming it was one of his servants.
The Lich's chant was interrupted by the iron ball knocking his head clean off his shoulders, killing him...for the second time.
With the chaos ending, it was safe to look around the room. The room seemed to be deserted, except for the skeletons lying around on the floor. All the skeletons seemed to have those same rings on their fingers. Even the Zombies and the Lich seemed to have them. And there were odd, old markings that were engraved on the walls, floor, and ceiling with pictures of a bat's face drawn on it.
Upon inspection, it would appear that the Lich's body was marked in the same carvings as were marked on the wall, in a language that seemed unidentifiable. His rotting his hand also had the same ring, but he had one on each of his five fingers.
The rest of the room seemed eerily empty. The only thing left inside was a table with a book on it, both untouched and covered in dust and mold.
The book seemed to have a few pages missing, but it was indeed read-able in a common language. Inside, the book spoke about how the cult worshiped the God, Grimcrypt, and how they wanted to serve him. The book would go on, listing members that, by now, would have been dead as they seemed to come from all kinds: poor nobodies to families of royalty. It started to talk about how the alter to this ritual was up the stairs, but the rest of the pages were missing.
The Lich's dead, rotten hand snapped off from the arm when Larius took it. The staff seemed to pulsate with a dark power as the fingers fell off of it. The staff, upon closer inspection, had the same markings that were upon the rings.
Meanwhile, outside the room, noises could be heard. It sounded like foot steps.

Regulus cursed under his breath, and reabsorbed the tendril of water into his reservoir. Thrusting his hand forward, he pressurized and released a beach-ball sized sphere of water from his reservoir, sending it streaming like a cannon shot towards the assembled zombies.
Regulus then quickly took a swig from the water skin at his belt. He might not get a chance later.
Nihil assumpseris, sed omnia resolvere!